I am going to investigate that if altering the temperature of Hydrochloric acid in the company of magnesium has an effect of how much hydrogen is produced.

Mohammed Ismail Ayub Chemistry Coursework

How Changing the Temperature of Acid Effects the Rate of Gas Produced

Introduction

My Prediction

I predict that as the temperature of the hydrochloric acid increasers the rate of reaction will rise and when the acid is at an average temperature the reaction will be decreased. This might happen because when the temperature increases the fraction of molecules that can provide the commencement energy needed for reaction becomes larger as the temperate increases. So if the atom of the acid has more energy that means that they will vibrate faster than normal and if they vibrate quicker they will hit or will collide. As the molecules will be colliding with each other, some atoms will escape because as the temperature increases, the atoms will be more violent and move rapidly. The atoms will escape into the air, from the reaction. This happens because the substances transfer energy from places where the temperature is higher to places where the temperature is lower. In this experiment, the two elements are magnesium and hydrochloric acid. In addition I think that if the temperature of the acid is less than 50c then the speed of reaction will be very slow. This might happen because the atoms of the acid haven't been heated. So that means that the atoms of the acid will have less energy or maybe no energy than normal so it will not vibrate a lot and it will not move or hit the magnesium atoms. So less vibration will be produced which means that almost all the acid atoms don’t react a lot with the magnesium ribbon.

Fair Test

To make the investigation fair and accurate there are certain things that I am going to change in my experiment and keep same in the experiment which will enable me to get accurate results. My aim was to find out if the temperature has an effect on the rate of reaction of the experiment. So the thing I will be changing in the experiment will be the temperature. The temperature will be changed with the help of a Bunsen burner. What I will keep the same in the experiment are the concentration of the acid, amount of acid, ...

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Fair Test

What I will measure and observe?

I will obtain a sequence of readings from the experiment. The temperature and readings will be taken twice, so the whole procedure will be done again. This will enable us to get a more accurate reading. All the readings and information will be presented clearly. The only thing I will be measuring is the amount of gas. The gas being produced will lower down the water levels. We can then measure the amount of millimeters the gas is at. I will take five reading on one temperature after one minute in five minutes with five different temperatures.

Apparatus

Stopwatch
Test Tube
Thermometer
Beaker
Bunsen Burner
Gauze
Measuring Cylinder
Tripod
Heat Proof Mat
Measuring Cylinder
Water
Metal (magnesium)
Acid (hydrochloric acid)
Delivery Tube
A Large Tub

Diagram

Method

I will set up my apparatus as shown in the diagram
Then will light the Bunsen burner and lay it under the gauze and will have heat mat underneath for protection.
Then will fill the tub with water which will reach unto 2/3 of the tub and will fill the measuring cylinder with water were it will reach to the top which will mark zero millimetres.
Then will tip the measuring cylinder in the tub with no air bubbles been inserted in the hydrochloric acid I will measure it to 20mm and will heat it up to the temperature I will be experimenting.
I will insert the magnesium strip and put a stopper in the test tube so the gas cannot escape and will put a delivery tube in the stopper going in to the measuring cylinder.
After that I will see how far the gas moves in the measuring cylinder every minute up to five minutes.
I will do the same investigation again but this time the temperatures of the acid will be different.

Results Obtained

First experiment

Second experiment

Average

I have worked out the average by add up the data from the two experiment and dividing by 2. You can see from my results that after each temperature, the amount of Hydrogen gas produce increases.

Conclusion

After I collected all my data from the experiments I then placed my results on a table and worked out the averages. Then I plotted them all on one graph because it’s easier to compare them. So, this is a change, which I did instead of putting them all on different graphs because it will be a waste of time doing it and also, it will be hard to compare the results.

The most reactive acid was the acid at 80ºC because the graph shows that it was the highest volume at the first minute in the first test, but then the volume got less, as it got higher than three minute. The reason for this might be because the atoms of the acid had more energy than the rest of the acid, and vibrated much faster than the others did. So that means that the atoms will vibrate or hit the piece of magnesium ribbon much faster and react quicker. At about four minute the volume stayed the same. This might happen because the acid (which was at 80ºC) reacted very fast with the magnesium ribbon at the beginning of the experiment that it finish the magnesium ribbon towards the end. This proves my statement, which I wrote in my prediction about the acid that is at 80ºC, will react with the magnesium ribbon much faster.

The acid at 70ºC reacted second fastest with the magnesium ribbon, but it went on increasing more than the acid at 80ºC. This might happen because the atoms of the acid, which was at 70ºC, didn’t have a lot of energy to vibrate faster with the magnesium ribbon so it didn’t start reacting very quickly at the beginning, so then it didn’t manage to finish the magnesium ribbon at the end.

The acid, which was at 30c temperature, was the last fastest because on the graph it’s the lowest line and increases gradually. This might happen because the acid didn’t have enough energy to vibrate faster and react with the magnesium ribbon faster and if we continued that experiment it would keep on going for at least another 30 second but still we would have not got any results.

Evaluation

My results have proved that the increase of temperature increases the rate of reaction. I have found out that temperature does have a significant impact on reactions and which it changes its rates. At the temperature 80oC, the amount of gas given off increases rapidly and at the temperature 30oC, the rate is much slower given from the results.

The Hydrogen gas given off from the reaction fills up the top part of the tube. This tells me that there is a change of mass, mass is loss as gas is evolved. When I think of a chemical reaction, we recognize that the difference in strengths between the bonds in the starting materials and those of the products may be different.

I think the way I worked was good and very fast but I don’t think I did it accurately because I had to rush it through to get time and do each experiment 2 times to get a more reliable results. So, I managed to get a more reliable result but not very accurate.

I got some anomalous results for the acid being at 80ºC because it should react faster than the acid at 30ºC because it’s hotter and it will have more energy, but it didn’t. It was completely the opposite. This might happen because I rushed it through and didn’t heat to the exact temperature or it cooled down faster than the acid at 70ºC maybe because the air conditioner was put back on again.

To improve my investigation I should have extended it and did more experiments to get a good set of results and to be more accurate while doing them. Also, I can improve it by getting all the amount of magnesium ribbon needed and all the hydraulic acid needed, and to use up the time I should put some test tubes in the water bath or in ice to get to the temperature needed while doing another experiment because then I wouldn’t have to wait and waste time for the acid to get to the temperature needed.